https://techcrunch.com/2021/12/21/ellume-bug-covid-results/

A security researcher found a Bluetooth vulnerability in a popular at-home COVID-19 test allowing him to modify its results.

F-Secure researcher Ken Gannon identified the since-fixed flaw in the Ellume COVID-19 Home Test, a self-administered antigen test that individuals can use to check to see if they have been infected with the virus. Rather than submitting a sample to a testing facility, the sample is tested using a Bluetooth analyzer, which then reports the result to the user and health authorities via Ellume’s mobile app.